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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
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            var btn = document.getElementById('btn');
            var uu = document.getElementById('uu');
            var li = uu.getElementsByTagName('li');
            btn.onclick = function () {
                for (var i = 0; i < li.length; i++) {
                    li[i].setAttribute('score', (i + 1) * 10);
                }
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                li[i].onclick = function() {
                    console.log(this.getAttribute('score') );
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</head>

<body>
    <input type="button" value="设置" id="btn">
    <ul id="uu">
        <li>成績</li>
        <li>成績</li>
        <li>成績</li>
        <li>成績</li>
        <li>成績</li>
    </ul>
</body>

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